Pneumatic action for pneumatic musical instruments



March 31, .1925.

53a, P. USTFSN PNEUMATIC ACTIOH FOR` PREUMATIC MUSICAL INSTRUMENTS Filed April 19. 1920 Patented Mar. 31, 1925.

UNITED STATES ADOLPH PETER GUSTAFSON, OF

CHICAGO, ILLIN PATENT. OFFICE.

PANY, OF CHICAGO, ILLINOIS,Y A CORPORATION OF ILLINOIS.

Application filed April 19, 1920.

To @ZZ whom t may concern:

Be it known that I, ADoLrH P. GUSTAF- soN, a citizen ot the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a vcertain new and usetul Improvement in Pneumatic Actions for Pneumatic Musical Instruments, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part oit this specification.

My invention relates to pneumatic actions ior pneumatic musical instruments, such as player pianos, piano players, and the like.

One ot the objects ot the invention is to provide a simple, practical and advantageous construction of pneumatic action.

Another object of the invention is to prevent leakage in the action, particularly in connectionwith the chambers for the valves controlling the power pneumatics of the action.

ln the accompanying drawings Fig. 1 is a cross section or' a pneumatic action embodying my present invention;

Fig. 2 is a similar cross section taken at one side ot the section ot Fig. 1;

Fig. 3 is a plan view of the action,

Referring to the drawings I show a wind. trunk 1 forming part ot a pneumatic action which is understood to be suitable for use in a player piano in connection with the piano action. This wind trunk 1 preterably comprises upper and lower members 1a and 1", respectively, which may be made of wood or other suitable material. These two members 1u and 1b are secured together, as b v screws 2h2, arranged in rows along the edges ot' said members as shown in Fig. 3. The upper member 1L is provided with a longitudinally extending groove or channel $3 and the lower member 11 with a longitudinally extending groove or channel. l, these two channels 3 and fltogethcr torni-- ing a windway 5 which is understood to be in communication with suitable wind inducing apparatus, such. as a pneumatic bellows, so as to produce in windway 5 a pressure either greater or less than atmospheric pressure, preferably a reduced pressure or partial vacuum.

Below the wind trunk l pneumatics (3*6 are arranged crosswise of the wind trunk 1, as shown in Fig. 3. Each of these pneumatics (5 is intended to operate apiano Serial No. 374,849.

action, the loose lea't 7 of the pneumatic for that purpose being preferably provided with a lug or projection S adapted to engage a projection on the sticker of the piano action.

The valve mechanisms for controlling pneumatics 6-6 comprise small pneumatics 9-9 arranged at intervals along the wind chamber' 5. Each ot these pneumatics 9 has a lower member 10 which rests on the bottom ot the wind trunk member 1h and is secured thereto, and a swinging member 11 hinged to the member 10, and having a bleed port nipple 11, said member 11 also carrying a valve stem 12 having a hooked end 13 carrying a valve 111. The valve 14 is arranged in a valve chamber 15 and rests on a valve seat 16. A cap or closure 17, in the form of a circular pasteboard disk, closes the top of the valve chamber 15, said cap 17 however, having an aperture 18 forming a port controlled by valve 14, and also forming an aperture through which the valve stem 12 may pass to permit engagement of the hook 13 with said valve 14:. The port or opening 18 controls communication between the windway 5 and valve chamber 15. A duct or passage 19 extends downwardly rom valve chamber 15, the upper end of said duct or passa-ge 19 forming a port also controlled by valve 14. The duct or passage 19 leads to a channel 20 extending along the under side ot the wind trunk 1, and communicating with the outside air. A duct or passage 21 extends between valve chamber 15 and interior ot pneumatic 6, whereby the latter may be put in communication with wind chamber 5 or outside air, according as valve 14 is in lower or upper position. Valve 14C is controlled by pneumatic 9, which is in turn controlled by a tracker board tube 29. and passage Q3 in member l".

As a nnittcr ot t'urther improvement the annular edge ot the cap or closure 17, or at least a substantial part ot that annular edge, is covered by the portion 2l of the upper member 11l ot the wind trunk 1, as best shown in Figs. 2 and In this way a very advantageous construction is made. The closures 17 are held in position by the portions or shoulders 24, as well as by the glue usually applied to the under sides of members 17, the latter being thus in eii'ect held between two substantial and rigid walls OIS, ASSIGNOR TO M. SCHULZ COM- Cil orabutments, so that changes fin pneumatic pressure even thou-gh quick l"andvlolent, cannot dislocate said members 17. Furthermore, leakage around the annular edges. of members 17 isprevented, thus effectively lstopping' leakage at points or areas where it might `occui.f=and considering the 'larzge number ot' members 17 1n an action, contributing materially 'toward 'producing an l of a closure forma.4 valve chamber, said.

closure being. provided `with an aperture forming a 'port controlled by the valvemember, and means substantially completely covering the edge portion of said closure..

2. In a pneumatic action'the combination of a wind trunk composed of upper and lower members,V the lower membenhaving valve chambers, closures `for said valve chambers, said 'closures being provided with apertures `forming valve ports, valves in said chambers and'means. for 'actuating said valves, the 'upper member of said wind trunk having portions=o\f'erlying and sub-y Vv-tions of said closures.

3. In apneumatic actionthe combination of a wind trunlrcomposed of upper and lower members securedtogether, the lower member being provided with valve chambers, disc-likemembers forming closures for said valve chambers and having apertures forming valve 'p0rts valves'in said chambers7 pneumatic means for controlling said i valves, said pneumatic 'means-.being .located j in the windway of the wind trunk 'and "being connected with the valves through said Vapertures in said disc-like members,

and pneumatics seeured'to the under side ot'v said wind trunk, the upper member ot said wind trunk having annular .portions covering` the joints of said closures with the under wind trunk member and also substantially entirely covering edge portions ot said closures.

In witness whereof, I hereunto subscribe my name this 8th day of April, A. D. 1920.

ADOLPH PETER jGUSTAFSON. 

